Optimal Wake Time is the total period of time baby is awake in any given daytime cycle, and includes time spent eating. Paying attention to OWT and making sure baby is asleep before becoming overly tired, is essential for great daytime naps which are essential for consistent nighttime sleep. OWT changes frequently in the first year, and it’s important to stay on top of those changes to prevent seeing any sleep disruptions.
Play time is considered the period between eating and sleeping. I think it’s very important for baby to have both parent-stimulated and individual play time each day.